Control panels are utilized in general for providing a means by which an operator can control or monitor mechanical and electrical apparatus. Such panels are generally equipped with manual switches for operating or regulating other equipment. Each switch or manual control is permanently labeled with regard to its particular function, thus affording the operator with an easy identification of the function of the switch.
Control panels of the keyboard type used with computers generally include the standard typewriter key layout, as well as many other special function keys. The identification of the keys, or the key functions, are typically engraved or labeled on the keys to allow the operator and those unfamiliar with the keyboard ease of entry of data into the processing system. It is common to mark certain keys with nonspecific designations, and to program the computer so that such keys can be used to provide a function in accordance with their programmed nature. The operator must either remember the special function of the nonspecifically identified keys, or be provided with an overlay cover or card which uniquely identifies the keys with respect to their currently programmed function.
Other types of keyboards, such as those used in case registers or similar equipment, are provided with a flexible cover on which an identification of the underlying keys is fixed. With this type of arrangement, the operator simply presses a permanently outlined area having the function identified thereon for accomplishing the desired result.
While the foregoing types of control panels are effective for their intended purposes, it is difficult to change the designations or identifications of the various keys without having to use an entirely new template, or requiring the operator to remember new or additional functions of the keys. Also, control panels and keyboards heretofore known in the art are used primarily for the one-way flow of information, e.g., from the operator to the processing system.
It can be seen that a need exists for a control panel with a programmable overlay display which uniquely identifies each switch, and which can be program controlled to automatically change the switch identification as the operator progresses in performing a programmed function. A need also exists for a keyboard display of information generated by the processing system, so that the operator can input information to the processing system, and the processing system can provide prompting information or instructions on the keyboard to the operator. A concomitant need also exists for a less complicated keyboard system in which only those switches are identified which are pertinent to a particular function or operation, such that the operator is not aware of the existence of the other keys whose functions are irrelevant to the particular operation.